As a part of environmental pollution measures, the development of a hybrid vehicle using a torque of a motor, a fuel cell vehicle, an electric vehicle, and so on has recently been in the limelight. The vehicles as described above are generally equipped with a power control unit (PCU) controlling power supplied from a driving battery (for example, voltage of 300 V) to be supplied to a motor in a desired state.
The PCU includes electric elements such as an inverter, a smoothing condenser, and a converter. If the electric elements are supplied with electricity, the electric elements generate heat. Therefore, the electric elements have to include a separate cooler.
As the relevant technologies, Japanese Patent Laid-Open Publication No. 2001-245478 (Published On Sep. 7, 2001, Title: Cooler for inverter) discloses an inverter using a semiconductor module having semiconductor devices of IGBT, etc. and a diode embedded therein and Japanese Patent Laid-Open Publication No. 2008-294283 (Published on Dec. 4, 2008, Title: Semiconductor Device) discloses a heat sink installed to contact a lower side surface of a semiconductor device and having a fluid flowing therein to exchange heat.
The single side cooling scheme has a limit of cooling performance. To improve the above problem, a dual side cooling scheme is devised. The dual side cooling scheme has a structure in which an element is inserted into a space between heat exchangers, and therefore the dual side cooling scheme needs to satisfy the conditions that an insertion interval of the electric element of the heat exchanger needs to be higher than a height of the electric element and the electric element and the heat exchanger need to be compressed to each other well to increase heat transfer performance of the heat exchanger.
As illustrated in FIG. 1, the heat exchanger based on the dual side cooling scheme may be configured to include tubes 20 positioned on both side surfaces of the electric element 10 and having a heat exchange medium flowing therein and tanks 30 coupled with both ends of the tubes and having the heat exchange medium introduced thereinto or discharged therefrom. However, the heat exchanger is coupled by brazing to fix the insertion space of the electric element and then insert the electric element, and therefore it has the disadvantage in that it is difficult to perform the insertion operation of the electric element.
Further, if the interval between the tubes is wide to facilitate the insertion of the electric element, the heat exchanger has a disadvantage in that the electric element and the tube are not compressed to each other well and thus the heat exchange efficiency is reduced.
Therefore, there is a need to develop a heat exchanger for cooling an electric element capable of facilitating the insertion of the electric element and compressing the electric element and the heat exchanger to each other well.